Orthoptic apparatus



' March 2, 1943. A. J. RADIN 2,312,930

ORTHOPTIC APPARATUS Filed Mayes, 1942 2 sheets-sheet 1 IN V EN TOR.

.77A ,Ex/1 /VDER RA o//v March 2, 1943.`- A. J. RADIN A 2,312,930

ORTHOPTIC APPARATUS Filed May 29, 1942 2 Sheets-Sheet 2 INVENTOR.

1 EXA No5/Q J R40/N Patented Mar. 2, 1943 imitan 'OFFICE ATENT My previous Patent No. 2,252,408, issued August 12, 1941, discloses an orthoptic device for exercising the orbital ocular muscles. The optical system for the left eye comprises an eyepiece and an objective which rotate continuously but in opposite directions. The optical system for the right eye comprises a continuously rotating objective which rotates in the same direction as the left eyepiece, and an harmonically rotating eyepiece. When the machine is operating, the eye muscles will periodically tension and relax in an endeavor to fuse or converge the lines of sight so that both eyes will see a single image. The variation in direction of the two lines of sight during the operation of the machine will depend on two factors:

1. The patient; thatis, on the shape of the eyeball, the shape oi the lens of the eye, and the ability to fuse; and

2. The prismatic effect of the optical systems. The speed of variation of the lines of sight will depend, of course, on the speed of movement of the lenses. If one eye is relatively weaker than the other, it will be necessary to correct substantially for myopia or hypermetropia or strabismus or whatever else the refractive ailment is, so that the patient can have binocular vision during operation oi the device.

I have found that some patients are unable to fuse for more than a small arc of rotation of the lenses. For example, a patient may theoretically be able to fuse for a distance of 15 degrees on either side of a vertical center line where the images coincide, or a total of thirty degrees. For the remainder of the cycle, 330 degrees, the lines of sight will not converge emmetropcally and the patient will see double. Due to the time lag and persistence of vision, the images will not fuse until a considerable time after the fusion area has been entered by the lenses, so that actually the duration of fusion may be degrees as the two images approach coincidence and degrees as they recede, a total of 25 degrees.

Some persons have so little muscle control that after fusion is broken they actually follow the movements of the two separate images throughout the cycle of 360 degrees, except for the instant when the images coincide. In such cases it is obvious that the eyes will obtain little bene fit from the exercise.

My present invention has for its primary object the provision of means for assuring fusion for any and every patient at all times during the operation of the machine. I obtain this result by alternately rotating the optical systems for Vmore particularly described.

Reference is had to the accompanying drawings, forming part of this application, wherein:

Fig. 1 is a front elevation of a preferred form of my invention.

Fig. 2 is a top view, partially in section.

Fig. 3 is a front elevation of another form of mechanism for converting continuous rotary movement into discontinuous movement.

Fig. 4 is a front elevation of another form.

On the horizontal base I is fixed the vertical support 2 which holds the lenses and related equipment. The left eyepiece 5 is associated with its objective 6, and the right eyepiece 'I with its objective 8'. If desired, only one eyepiece and one objective may be used, or two or more of each, or only two eyepieces or two objectives, as conditions may require.

Motive energy is obtained from the motor 30 by means of the crank 3|,V the connecting rod 32, and the rack 33. This rack 33 meshes with the pinion 34 which is freely rotatable on the shaft 26. The gear I1, fixed on the shaft 26,v

drives the gears I8, I9, and 20. The members I9 and 2B impart rotary `movement to the left objective 6 and the right objective 8, respectively. The gear 2U also meshes with the pinion 22 fixed on the rear of the shaft 23. The shaft 23 is unitary, and on its front end has xed a spur 24 which meshes with the gear 25. The latter drives the left eyepiece 5.

At the front end of the shaft 26 is rigidly attached a radial arm 21. A link is pivoted at one end to the arm 21 and at the other end to a horizontal rack 28. The rack 28 meshes with the gear 29 which drives the right eyepiece 1. Consequently, the right eyepiece 'I will be given a harmonic rotation of degrees back and forth for each rotation of the gear II and the lenses 5, 6, and 8. The arm 21 is adjustable radially of the shaft 26, thereby controlling the rate of harmonic rotation.

A clutch 4I is movable longitudinally of the shaft 26, to which it is keyed to rotate therewith. One side of the clutch has teeth with which to engage complementary teeth or grooves in the side of the pinion 34, so that engagement therewith will transmit energy from the motor 33 through the pinion 34 and the clutch 4I to the shaft 26. The other side of the clutch 4I also has teeth with which to engage complementary teeth or grooves in the adjacent side of the sprocket wheel I, which is freely-rotatable on the shaft 26. The sprocket wheel 5I is given continuous rotary motion by the motor 30 by means of the sprocket chain 52 and the sprocket spur 53 on the shaft of the motor 30. Thus, the gear 3d and the sprocket wheel 5| are always in motion when the motor operates, and the shaft 25 turns whenever the clutch 4l engages either the gear 34 or the sprocket wheel 5l.

When the clutch handle 40 is actuated to move the clutch 4I forward (toward the bottom of Fig. 2), the clutch will engage the gear 34, and consequently the lenses 5, 6, and 8 will be rotated harmonically, while the right eyepiece 1 will be given a harmonic movement displaced in 'phase with respect to the harmonic movemnt'impart ed to its associated objective 8. When the clutch handle 40 is moved to engage the clutch'l withthe sprocket wheel 5l, the lenses 5, 6, and 8 will rotate continuously and the lens 'l harmonically. When the clutch is in neutral, the shaft 27S1`will not turn and the lenses will be stationary.

Ihe front end of the shaft of the' motor 33 has fixed to Vit a disc E0 and a crank arm $2. The crank 3| is fastened by a set screw to the crank arm'52. Thus, rotation of the motor shaft will rotate the disc 63, revolve the crank arm 62 and the'crank 3|, and reciprocate the" rack 33 by means of the connecting rod 32. The throw of the crank 3l may be varied by adjusting the positionofthe crank 3| in the crank arm 52. The amount of variation maybe indicated by markings 63 or other indicia on the crank arm 52.

When the clutch 4I is pulled forward, it will engage with the gear S4, which is driven by the reciprocating rack 3,3. 'Ihe clutch il and the keyed shaft 2`6 wi ll then rotate back and forth, the degree depending on' thev dimensions of. the gear 3 5, the rack 33, the connecting arm 32, the crankj 3j, the'crank arm 62 and the disc 60;l All these dimensions are rlxjed.- except for the throw o f the crank 3l, which; as described, can

be varied. "lherefore, the degree of rotation of` the. gear lflandithe connected lens gears will de-- pendion' the Aadjustment of the crank 3l in the crank arm 62,. The harmonic rotation of the right eyepiece '1 is always a mathematic function of tlfiemovement ofthe shaft26.

The'jspeed of movement of the gears and lenses will b 'e controlled by utilizing arheostat to change` 'the speed of the motor.

Wirth my improved apparatus, I can use a single set of lenses for a wide range of ocular abnormalities, it being merely necessary to have such lenses that fusion can be attained at some one position ofthe lenses. The machine is started with the clutch 4j pulled forward sothat the gear 311 will be engaged' to give harmonic rota# tion to all Vthe lenses. The extent of oscilla,- tion may be, for exampleve degrees each side of center, if the patient can hold fusion for atA leastthat extent. 'As the lenses go back and forth, the muscles willtense andrelax rhythmically, leading 'to the 'benets I have described.

The exercise is continued for the desired time' during which fusion is retained constantly. Subseduently,'the crank 3| is moved outwardly in the crank arm 62 t'o obtain a greater oscillation of the lenses, and the patient will receive aA slightly greater degree of exercise. I have foundl continuously rotate the lenses 5, 6, and 8 and thereby give a greater degree of exercise. In addition, or in lieu thereof, the lenses may be replaced to give a diierent refractive result.

In Fig. 3 I show another way of obtaining variable reciprocatory motion from the motor 30. An eccentric strap 1| iixed to the end of the connecting rod 32 is actuated b'y the eccentric 12. The eccentric 'l2 is slotted at 13 to permit adjustment of the eccentric throw about the motor shaft. This slot 13, too, may have indicia to guage the degree of oscillation of the lenses.

Fig. 4 illustrates still another modification. The disc 66 xed to the motor shaft has several openings 83 to which one arm of a bell crank 84 may ben fastened by means of a set screw. The

' crank Sli is pivoted at 85, and the other end of the crank 84 is pivoted at 86 to the connecting arm 32. The pivot 86 may be varied, and so may the Pivot 85, to permit greater variation.

Having described my invention, what I now claiml as new and` desire tol protect by Letters Patent is:

1. In a device of the character described, an eyepiece'and objective for each eye, means for turning the lenses about their optical axes to vary the directions of the lines, of` sight, and means for controlling the turning means so. that the lenses are' turned automatically only apredetermined amount.

2. In a device of the character described, an optical system for each eye, a motor, means connected to the motor for harmonically rotating one of theoptical systems, and means connected to the motor for optionally turning the` Vother optical system either harmonically or ccnl tinuously.

3.' Inv a device of the character described, an optical'system for each eye, means.k for turning4 each system to vary the direction of the lines of sight, and means for automatically reversing the turning movement when, lajpredeterrnined point has beenreached.

4; Inv a device of thek character described, a

setof lenses, means for imparting toY oneof-l said` lenses continuous motion and to another lens. discontinuous motion'and means for optionolly changing the motion of the continuously drivenl lens to discontinuous, wherein'the last-'claimed means also changes the motion of the discontinuously driven lensY to another discontinuous motion which is afunction o'f the motion of the first-mentioned lens.

5. In a device offthe character, described, al

lens for one eye, a lens for the other eye,'ineans harmonic motion, and means vfor imp artln'gtov the other lens `at thesame time either harmonic or double harmonic motion. 4'

6. In a device of the character described, alii/ aligned eyepiece and objectivef'for' eachf eye,

means for imparting lrotation to one eyepiece inA an opposite direction' to thratof `its objective and1v in the same direction as thother .objective and exactly in phase Vwith'both,` means for impartingto tnejotn'er objective motion which is "always harmonic in relation tothe other three lenses, and means for making the. motion of the other three lenses either harmonic `orcontinuous.`

'7. The combination set forth in Yclaim 6 wherein the. lastfclaimed means comprises a motor, a disc xed on,` the motorshaft,- va crank.

arm'xed tothe discyan adjustablecrankslide.

able inv thel crankvv arm, a connecting l.rod 'pivoted `at one end to thecrank,4 andamechanisrnnfrf.

transmitting the motion of the other end of the connecting rod to the lenses.

8. The combination set 'forth in claim 6, wherein the last-claimed means comprises a motor, a disc fixed on the motor shaft, a crank arm fixed to the disc, an adjustable crank slidably fastened to the crank arm, a connecting rod pivoted at one end to the crank, a sprocket Wheel driven continuously by the motor shaft, and means for optionally transmitting the continuous motion of the sprocket wheel or the discontinuous motion of the connecting rod to the related three lenses.

9. In a device of the character described, a lens, an objective, and means for imparting harmonic oscillations to the said lens and to the said objective, said harmonic oscillations being displaced in phase relative to each other.

7:10. In a device of the character described, an eyepiece and objective for each eye, a motor, nieans connected to the motor for harmonically rcitating both objectives and one eyepiece in phase with each other and for imparting a harmonic movement to the second eyepiece, said last-named harmonic movement being displaced in phase relative to the harmonic rotations irnparted to both of the said objectives and to the said one eyepiece.

ALEXANDER J. RADIN. 

